1. Field of the Invention
The present invention relates to electronic equipment and a data processing method therefor, and particularly to electronic equipment for receiving data through a bus and a data processing method therefor.
2. Description of the Related Art
Recently, electronic equipment such as a personal computer, a digital video camera or the like which can mutually communicate data through an IEEE1394 bus has been developed, and it is expected that the number of types of such electronic equipment will be increased in the near future.
The content data (audio data, video data, etc.) communicated on the IEEE1394 bus are digital data. In order to prevent the content data from being copied endlessly, information indicating whether the copy of the data concerned is allowed or not (copyright information) is described at a predetermined position in an isochronous packet of the content data. In the case of electronic equipment connected to the IEEE1394 bus, even when a user makes an instruction such as recording or the like of data which are prohibited from being copied on the basis of the copyright information, the instruction (recording or the like) is not executed, whereby any copy of the content data concerned is not produced.
If a user can recognize the copyright information as described above, the user does not make any instruction on the copy such as recording or the like for content data which are impossible to be copied, and this is convenient. However, there is no electronic equipment having a function of notifying the user of the copyright information set in the content data communicated on the IEEE1394 bus. Furthermore, when content data transmitted from a transmission side are encrypted, the content data thus transmitted could not be decoded if a decoding key cannot be correctly generated due to a time lag of transmission/reception timing.
It is therefore an object of the present invention to provide electronic equipment which resolves the above-mentioned problem.
It is another object of the present invention to provide a data processing method for electronic equipment which resolves the above-mentioned problem.
It is further object of the present invention to provide a data processing method which resolves the above-mentioned problem.
According to the present invention, there is provided electronic equipment for receiving at least data containing content data transmitted in the form of a packet through a bus, comprising: a receiving portion for receiving the data transmitted in the form of a packet through the bus; a judgment portion for extracting copyright information from data supplied from the receiving portion, and judging on the copyright information thus extracted at least whether the content data contained in the data thus received are allowed to be copied or not; and an output controller for receiving the judgment result from the judgment portion and generating and outputting notification data corresponding to the judgment result.
According to the present invention, there is provided a data processing method for electronic equipment for receiving at least data containing content data transmitted in the form of a packet through a bus, which comprises the steps of: receiving the data transmitted in the packet form from the bus; extracting copyright information from the data received; judging on the basis of the copyright information thus extracted at least whether the content data contained in the data received are allowed to be copied or not; and generating and outputting notification data corresponding to the judgment result.
According to the present invention, there is provided electronic equipment for receiving at least encrypted data containing content data and attribute information indicating the attribute of an encrypting key transmitted in the form of a packet through a bus, which comprises: a receiving portion for receiving the data transmitted in the packet form through the bus; a judgment portion for extracting copyright information from the data supplied from said receiving portion and judging on the basis of the copyright extracted at least whether the content data contained in the data received are allowed to be copied or not; and an output controller for receiving the judgment result from the judgment portion and generating and outputting notification data corresponding to the judgment result.
According to the present invention, there is provided electronic equipment for receiving at least encrypted data containing content data and attribute information indicating the attribute of an encrypting key which are transmitted in the form of a packet through a bus, which comprises: a receiving portion for receiving the data transmitted in the packet form through the bus; a key generator for generating plural decoding keys; a decoding portion for performing decoding processing on data supplied from the receiving portion on the basis of a decoding key from the key generator; and a controller for selecting one of plural decoding keys output from the key generator on the basis of the attribute information extracted from the data output from the receiving portion.
According to the present invention, there is provided a data processing method using at least two electronic apparatuses which are connected to each other through a bus, one apparatus serving as a reception side at least receiving encrypted data containing content data and attribute information indicating the attribute of an encrypting key which are transmitted in the form of a packet from the other apparatus serving as a transmission side, which comprises the steps of: receiving the data transmitted in the packet form through said bus on the electronic apparatus serving as the reception side; generating plural decoding keys on the electronic apparatus serving as the reception side; performing decoding processing on the data received on the basis of the decoding key generated in the electronic apparatus serving as the reception side; and selecting one of plural decoding keys generated on the basis of the attribute information extracted from the data received on the electronic apparatus serving as the reception side, and using the decoding key thus selected for the decoding processing.